JPH0292029A - Signal relay device for space flying body - Google Patents

Abstract

PURPOSE: To reduce the weight, the size and its output loss of a repeater and the complicated configuration of the repeater by designing the signal repeater for space flying body provided with a channel selection circuit network CSN having lots of 1st ports and a distribution output amplifier SRAM having a circuit network consisting of balanced amplifiers. CONSTITUTION: A CSN 2 acts like delivering a signal from any selected port among input ports 24-31 to any selected port among output ports 24-31. An SPAM 3 is acted such that a signal received by any of input ports 44-51 from the CSN output ports 24-31 is distributed to all amplifiers 61 and all available amplified outputs are used by any of 2nd output ports 52-59 or their combinations. Thus, band width and output resources are distributed with more flexibility at less installation cost through the combination of the SPAM and the CSN.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a signal repeater for a spacecraft such as a communication satellite.

A need has arisen for a spacecraft payload, such as a communications satellite, that significantly increases the flexibility of communications. This has been brought about by the trend of increasing the number of coverage areas and therefore the need for satellite antenna beams. This trend can be summarized as follows. (11) Typically, satellites cover large areas of the Earth's surface using relatively small antennas on the satellite due to limitations in satellite technology.The effective power output (EIRP) of the satellite is and to increase the input sensitivity (G/T: gain-to-noise-temperature ratio), the satellite antenna gain can be increased with small beams. Many such beams are used, and as with the first large beam, the satellite antenna gain can be increased with small beams. The entire surface was covered. Figures 1(a) and 1(b) illustrate an example of this conventional multiple beam coverage technique.

(2) The first production of a practical communications satellite was designed and used for international communications and essential nearly global coverage. Recently, communications satellites have been used by each country or relatively small group of countries to provide local or interregional communications.

- A small coverage area is required for these applications.

However, the economic functionality of local communications satellites poses problems, with the pooling of communications satellite resources among several countries allowing one or the other country to use them at different times during the satellite's life. Therefore, a trend has arisen to reshape the communications satellite resources. This created the need for a large number of separate antenna beams with uncertain distribution of satellite resources (bandwidth and power) among these beams.

Another trend related to this use of many small antenna beams is that communication satellites are becoming larger and have a larger number (5
0) to carry a transponder. This results in the need to have the flexibility to connect up to 50 transponders and, for example, 20 to 40 antenna beams.

The lifespan of satellites has increased from 2 to 3 years to 10 years in the last 20 years.
It was extended to 2015 or 2015. The ability to accurately predict communications requirements (along with the three-year satellite construction period) became a major challenge.

Another relevant factor is as follows.

(ll) The trend to use smaller ground stations is a result of the balance of relative costs between satellites and ground stations in the overall system. This includes a reduction in the effectiveness of the satellite resources, especially as the use of more satellite power per link is required for operation with large ground stations. mode, meaning that it actually has more available bandwidth than can normally be usefully used.

(2) Small and inexpensive ground stations also encourage the use of a 5 cpc operating mode (one channel per carrier), which means that many carriers are within the same satellite transponder bandwidth at the same time. There is. Each carrier supports its ground station group. To avoid intermodulation distortions that dominate link performance, the satellite's HPA (High Power Amplifier) is typically
It must operate in a linear mode, called off.

A high-power amplifier (HP
A'! ) and the transmission antenna beam, it was proposed to address these demands and trends, but this proposal suggests that the operational capabilities and communications flexibility of the satellite are limited by the weight, size, complexity, and was severely limited by the large output losses of the switching network to be used.

SUMMARY OF THE INVENTION It is, therefore, an object of the present invention to provide a signal repeater for a spacecraft that minimizes the weight, size, complexity, and power loss problems described above.

Another object of the present invention is to provide a signal repeater that improves the operational flexibility of a spacecraft, such as a communications satellite, on which it is attached.

These and other advantages of the invention will become more apparent from the following description, in which preferred embodiments of the invention are disclosed.

According to the present invention, the first input port is connected to a plurality of first output ports by a filter circuit that can selectively act on the signal at one of the selected first input ports. a channel selection network (CSN) having a number of said first input ports operable to communicate to a first output port of the channel selection network (CSN); and a number of second input ports receiving signals from the number of first output ports; The amplification of the signal received at any one of the plurality of second output ports and the second input port is divided by all the amplifying devices and sent to any one of the second output ports. A spacecraft signal repeater is provided that includes a split power amplifier (SPAM) having a network of balanced amplifiers that can be connected to utilize the full available power or a combination thereof.

The channel selection circuitry comprises n filters, each of said n filters having a series of one or more connected to an associated one of the first input ports via one or more switches 11. a two-pole, two-way on/off switch and having m output conductors, each of the m output conductors connecting the other pole of one switch of one or more filter circuits to the associated first output port. Advantageously, they are connected together.

Each filter circuit has a bandpass filter from which the or each switch of the circuit is connected to an associated first input port, such that during operation of the device the signal received at the cylinder 1 input port is combined at the second input port. Preferably, the output signal is transmitted and transmitted with a desired relative amplitude to equalize differences in pass losses between the filter circuits, and to produce the desired output at the second input port.

Typically, the value of n is greater than m.

Preferably, the effective amplification power of the split power amplification module is the sum of the amplification power of the individual amplification devices.

Each amplifier is a balanced amplifier, and the two second input ports are connected to the two amplifiers through a first 90° hybrid coupler, and the outputs are connected to the two amplifiers through a second 90° hybrid coupler. Preferably, the capacitor is connected to two output ports, and a signal inputted from one of the first output ports to one of the second input ports is transmitted to a second output port on the diagonally opposite side.

The split-output amplification module circuitry includes a number of balanced amplifier devices including an additional 906 hybrid coupler between the second input port and the first coupler and between the second coupler and the second output port. It is convenient to be installed in

Another feature of the invention is a spacecraft having a signal repeater.

The combination of a channel selection circuit wA (CSN) and a split power amplification module (SPAM) previously required the use of a large number of fixed power, fixed communication capacity transponders pointing to the required coverage antenna beam. Particularly suitable for use in communications satellites. C3N allows individual signals or channels to be distributed to the input ports of the SPAM, and the SPAM amplifier
The signals transmitted to each output port of M are amplified separately to make best use of the available amplification power.

BRIEF DESCRIPTION OF THE DRAWINGS For a better understanding of the invention, and for illustrating how the invention may be carried out to advantage, reference is made to the accompanying drawings.

The signal repeater of the present invention, generally indicated by the numeral 1 in FIG. 10, is intended for use in a spacecraft, and will be described below as being used in a communications satellite type spacecraft. The device 1 basically comprises a channel selection network (CSN), generally designated 2, and a split power amplification module (SPAM), generally designated 3.

C3N is a selectively acting filter circuit 14 to 2;
It has a number of first input ports 4-13 connected by number 3 to a number of first output gates 24-31. C
3N is any selected input port 4 to 13
signals are transmitted to any selected output port 24-31. C3N comprises n filter circuits each consisting of a series of one or more two-pole two-way on, off switches 32 connected to an associated one of the input ports 4 to 12 via one pole 32a, and 1 to the associated one of the output ports 24 to 31
A series of m output conductors are provided which connect to the other pole 32b of one switch 32 of one or more filter circuits 14-22.

Preferably n is greater than m, and in Figure 2a n! 10
and, on the other hand, mw3. However, n and m can be any desired numbers; in FIG. 4, C3N has n=9 and m=8. Each filter circuit 1
4 to 22 have a bandpass filter 41 and a circulator 41a, from which the or each switch 32 of the circuit
are connected to the associated input ports 4 to 12.

During a normal payload period, C3N2 performs demultiplexing, channel connection switching and multiplexing functions. The basic structure of C3H is shown in Figure 2a. This example shows how 10 channels are divided into 8-vote SPAM.

In the initial mode or off-mode, all switches 32 disable any filter circuitry and therefore the signal from output 2.
4 to 31 so that they are not connected. When it is desired to transmit a particular signal to the output, the switch 32 that intersects the circuit carrying the signal and the conductor connected to the output are set to the on position.

Although it is not possible to set more than one switch to the on position in any circuit, any number of switches in the conductor can be set to the on position. Both of these modes are illustrated in Figures 3a and 3b by the signal paths shown in bold. In Figure 3a, the signal enters the conductor at 42 from the previous circuit and exits at port 25 when no further signal is applied. In FIG. 3b, the signal enters the conductor at 43 from the previous circuit and is combined in filter circuit 22 with the signal entering circuit 22 at input 12 and exits port 25.

The size of C3N depends on the number of circuits available and the number of outputs to which these circuits must be directed. If it is never necessary to direct a signal to a particular output, the switch 32 and conductors that intersect the circuit in question are removed and bypassed. An example of this is shown in FIG.

SPAM3 has a number of second input ports 44-51 receiving signals from first output ports 24-31 of C3N2, a number of second output ports 52-59 and connecting input ports 44-51 to output ports 52-59. It has a circuitry 60 of a balanced amplifier device 61 (FIG. 5) that can be used. SPAM connects C3N output ports 24 to 31
The amplification of the signal received from to any one of the input ports 44 to 51 is divided by all the amplification devices 61 and the total amplification available by any one of the second output ports 52 to 59 or a combination thereof. Act so that the output is used.

SPAM 3 is thus a number of amplifiers connected so that they act as a single amplifier with one or more inputs and outputs.

The effective output of the SPAM is the sum of the outputs of the individual amplifier devices 61 as shown diagrammatically in FIG.

The SPAM 3 consists of several small elements combined in parallel, the smallest of which is a two-bottom SPAM shown in FIG. 6, commonly referred to as a balanced amplifier 61. The 4-vote SPAM is a balanced combination of two of these, as shown in FIG.

This technique has been extended with successively higher order composite SPAMs, and an eight-port device is shown in FIG.

Each balanced amplifier 61 has two amplifiers 63, 64 connected via a first 90° hybrid coupler 62, preferably a 3 dB coupler, the output of which is connected via a second 90° hybrid coupler. 65 to two second output ports 52 and 53, and a signal received at one of the second input ports 44 is transmitted to the diagonally opposite second output port 53.

The SPAM network is as shown in Figures 7, 8 and 9.
A large number of balanced amplifier devices 61 having a nested structure can be provided. In these examples, additional 90" hybrid couplers 66-69 are provided between the second input ports 44-51 and the first coupler 62 and between the second coupler 62 and the second output ports 52-59. It is being

Signals entering any of the input ports 44-51 are split by a hybrid coupler 62, 66.68 network and passed through each amplifier device 63, 64 of the device. Next, the output circuit network high hybrid coupler 67.6
9 recombines the elements of each signal to the corresponding output port 52
to 59 are output. The signals input to each port are amplified by a fixed gain, so a difference in the input levels of the signals results in a corresponding difference in the output levels. In this way the full available power of the payload is best used.

If more amplifiers than ports are needed, the network can be trimmed down by removing unused hybrid couplers as desired.

FIG. 9 shows a 4-port SPAM amplification device.

A flexible repeater structure is formed by combining a C3N and a SPAM in series, as schematically illustrated in FIG. A series of bandpass filters 41 are included at the input of C3N. The signals are then reliably combined and transmitted to the SPAM part 3 with the correct relative amplitude. This accomplishes two purposes. First, to equalize the path loss differences from one channel to the next, and second, to generate the required relative power differences at the inputs to SPAM3.

Increasing or decreasing the number of channels and/or output ports are handled separately as previously described.

Thus, SPAM allows the total radio wave power available on the satellite to be divided in any proportion between the signals passing through the satellite, which is a fixed amount previously required, e.g.
It is not fixed at 0 watts.

This essentially refers to a device for flexibly distributing the satellite's output calyceath.

C5N is a device that flexibly distributes vibration frequencies to different channels of a satellite, reducing the frequency for example 72
It is not fixed at a fixed amount of MHz. This is a device that flexibly allocates satellite bandwidth to base fishing and main fishing.

Since communications satellites essentially had only two resources to provide communications to their users: bandwidth and power, the combination of SPAM and C3N could combine these two resources more flexibly and in a way that was previously possible. You can allocate the cost of equipment at a lower cost than you would otherwise have.

Various modifications and changes may be made to the embodiments of the invention shown and described within the scope of the invention as defined by the claims.

[Brief explanation of drawings]

Figure 1a is a schematic diagram illustrating a multiple beam coverage technique showing the use of conventional three-point beams A, B, and C;
FIG. 2b is a diagram of an example of a channel selection network (CSN) for use in the signal repeater of the invention; FIG. Figure 3a is a schematic diagram showing the switch of the network of Figure 2a in on and off positions, which is also applicable to Figures 3 and 4; Figure 3a shows the output of one filter circuit to the next unapplied circuit; Fig. 2a is an enlarged cross-sectional view of C3N in which the signal transmission path of the conducting wire is shown by a thick line, and Fig. 3b is a thick line showing the signal transmission path that is added to a signal input to one filter circuit and input to the next filter circuit. A diagram similar to FIG. 3a, FIG. 4 is a simplified C3N diagram used in the signal relay device of the present invention, and FIG. 5 is an overall diagram of the split power amplification module (SPAM) used in the signal relay device of the present invention. FIG. 6 is a block diagram showing the overall type of division to be formed; and FIG. 6 is a diagram of a balanced amplifier device forming a part of the SPAM used in the signal relay device of the present invention. FIG. 7 shows a nested balanced amplifier device forming part of a SPAM used in the signal relay device of the present invention, and FIG. 8 is a diagram similar to FIG. 7 showing an 8-point, 8-stage balanced amplifier device. FIG. 9 is a diagram similar to FIG. 8 showing a 4-bot, 8-stage SPAM, and FIG. 1O is a block diagram of the signal relay device of the present invention. 1... Signal relay device, 2-... Channel selection circuit network 3-... Divided output amplification module, 4-13...
---First person port, 14-23--Filter circuit, 24-31--First output port, 32...
switch. 44-51--2nd person capo, 52-59...
・Second output port, 60.61-...-amplifier, 6
2゜63.64---Amplifier, 65,66.67゜69--- Coupler drawing (no change in content) Fig, Ha no f u' ni J, 7(b) 10,000th place Fig, 5゜Fig, 6゜Fig, 7゜Fig, 4゜in5 l 1 so U 5] Fig, 8゜Fig, 9゜Procedure II'rrj Original (spontaneous) September 1999

Claims (1)

[Claims] 1. Selecting a signal at any one of the first input ports that is a first input port and is connected to a plurality of first output ports by a filter circuit that can selectively act. a channel selection network (CSN) having a plurality of said first input ports operable to communicate to any one of said first output ports, and a plurality of second an input port, a plurality of second output ports, and a second output port in which the amplification of a signal input to any one of the second input ports is divided by all the amplifying devices; A spacecraft signal repeater comprising a split power amplifier (SPAM) having a network of balanced amplifiers that can be connected to utilize the full available power by any one or combination thereof. 2. The channel selection circuitry has n filters, each of the n filters being connected to an associated one of the first input ports via one pole of one or more switches.
consisting of a series of two or more two-pole, two-way on/off switches;
and further comprising m output conductors, each of the m output conductors connecting the other pole of one switch of the one or more filter circuits to an associated one of the first output ports.
The device described. 3. Each filter circuit has a bandpass filter, from which the or each switch of the circuit is connected to the associated first input port, and during operation of the device the signal received at the first input port is transmitted at the second input port. 2. The apparatus of claim 1, wherein the combined and transmitted signals are transmitted at a desired relative amplitude to equalize differences in pass loss between the filter circuits to produce the desired output at the second input port. 4. The device of claim 4, wherein the value of n is greater than m. 5. The apparatus of claim 4, wherein the effective amplification output of the split output amplification module is the sum of the amplification outputs of the individual amplifier devices. 6. Each amplifier is a balanced amplifier, and the two second input ports are connected to the two through a first 90° hybrid coupler.
an amplifier, the output of which is connected to the second output port via a second 90° hybrid coupler, and a signal input from one of the first output ports to one of the second input ports. 6. The apparatus of claim 5, wherein is transmitted to a diagonally opposite second output port. 7. The split-output amplification module network comprises a number of balanced amplifier devices in a nested configuration, including an additional 90° hybrid coupler between the second input port and the first coupler and between the second coupler and the second coupler. 7. The device according to claim 6, wherein the device is provided between the output port and the output port. 8. A spacecraft comprising the signal relay device according to claim 7. 9. A communication satellite comprising the signal repeater according to any one of claims 1 to 8.